Solutions for fatigue analysis from finite element analysis (FEA) of metallic components have been available for many years. An important part of the analysis for linear structures such as metallic components is a procedure called “scale and combine”, which allows one to convert from raw road load data to stresses and strains. In this procedure, a series of unit load cases is modeled in FEA and can then be used to reconstruct stress or strain histories for a multiaxial input signal.
Nonlimiting examples of fatigue analysis solutions for metallic components are described in each of: Conle, F. A., and C-C. Chu. “Fatigue analysis and the local stress-strain approach in complex vehicular structures.” International journal of fatigue 19.93 (1997): 317-323; Braschel, Reinhold, Manfred Miksch, and Rolf Schiffer. “Method of monitoring fatigue of structural component parts, for example, in nuclear power plants.” U.S. Pat. No. 4,764,882. 16 Aug. 1988; Yim, Hong Jae, and Sang Beom Lee. “An integrated CAE system for dynamic stress and fatigue life prediction of mechanical systems.” Journal of Mechanical Science and Technology 10.2 (1996): 158-168; and Conle, F. A., and C. W. Mousseau. “Using vehicle dynamics simulations and finite-element results to generate fatigue life contours for chassis components.” International journal of fatigue 13.3 (1991): 195-205.
For many, FEA has become an essential part of maturing and qualifying design concepts, providing a cost-effective and proven basis for justifying investment in physical prototypes and testing. However, conventional fatigue analysis solutions do not work well for elastomeric components because of their macromolecular structure. In particular, the scale and combine method is not suitable for rubber parts, because of material and kinematic nonlinearities in rubber.
Rubber or elastomeric components exhibit unique behavior and require specialized analysis methods. Developing a durable elastomeric component often involves expensive, time-consuming, trial-and-error iterations. There has been a long-felt, but unsolved, need in industries such as automotive, defense, transportation, heavy equipment, offshore, medical devices and consumer products, for a solution to put developers in control of durability issues early in the development cycle, when the greatest opportunities to influence performance exists.
With regard to rubber components such as bushings, tire treads, seals, etc. used in an automotive setting, it is known that road load signals are too lengthy to use for full FEA of the rubber components. However, a full strain history remains desirable for damage calculations by FEA.
There is a continuing need for a method and system for efficiently obtaining strain and stress histories at potential failure locations in a rubber component, based on a given time-varying load data signal such as a road load input signal and FEA.